Hydrophobic benefit agents, especially perfumes, but also skin lightening, agents, sunscreens, anti-aging compounds etc. can provide benefits to the skin or to hair. At present, however, it is extremely difficult to achieve high levels of deposition and/or to enhance the effect of these agents when delivered from personal product compositions, including, but not limited to personal wash liquid cleansers and personal product bars.
While this and co-pending applications are described with personal product language, to the extent the structured benefit agents can be used in a variety of compositions where deposition by benefit agents is desirable (e.g., hair, deodorant), the claims are intended to be read expansively and limited only by structuring component.
Applicants have now found that the use of structured benefit agents (the structured benefit agent compositions are separate from the “separate” hydrophobic benefit agents found in the same final products) helps to enhance the effect of separate hydrophobic benefit agents. The structured benefit agent may carry or entrap the separate hydrophobic benefit agents (e.g., perfumes, sunscreens), or the SHBA may have been added separately rather than in a premix used to form the structured benefit agent. In the presence of the structured benefit agent, the separate hydrophobes display enhanced benefits compared to the effect of the same hydrophobic benefit agents which are delivered in formulations where structured benefit agent is not used. According to the invention, preferably the benefit agent which is being structured and the structuring material (e.g., crystalline wax, hydrogenated oil or fat) are separate components.
By specifically selecting particular crystalline structurant or structurants (i.e., so that the crystals have specifically defined aspect ratios), and by separately preparing the structured benefit agent as a premix in the manner described (i.e., separate preparation and delivery in a molten, semi-molten or solid state), use of the structurant vehicle provides enhanced attributes (e.g., enhanced perfume impact) of the separate hydrophobe.
Specifically, the invention relates to use of benefit agent(s) structured by crystalline structurants selected from the group consisting of natural and synthetic crystalline structuring materials (e.g., waxes), wherein, when the structured benefit vehicle is separately prepared before combining with the personal product composition, it provides enhanced properties (e.g., total perfume delivered or deposited) to a separate hydrophobic agent in the composition (which SHBA is either carried on/with the structured benefit agent, or is added separately from a premix used to form the structured benefit agent but is still found in the final composition). The enhanced properties of the SHBA may be the result of enhanced deposition (as disclosed in copending applications) of the “structured” benefit agent (different than separate hydrophobic benefit agent) or some other mechanism but this is not critical to the invention.
Among the structurants which may be used are natural or synthetic crystalline waxes. Among natural waxes are included petroleum derived waxes such as paraffins and microcrystalline waxes; as well as animal and plant (vegetable) waxes. Among the synthetic crystalline waxes which may be used are crystalline polymers such as polyethylene. Structurants may further include natural or synthetic hydrogenated oils or fats, fatty acids, fatty alcohols, salts of fatty acids, hydroxy fatty acids and fatty acid esters.
Some prior art references purport to use rheological parameters to select oils or oil blends to be used for improving deposition or providing favorable sensory feel.
U.S. Pat. No. 5,674,511 to Kacher et al., for example, describes the use of solubility parameters and four rheological parameters to select benefit agents (i.e., oil or oil blends) that can be used in moisturizing cleansing formulations to improve deposition and provide favorable sensory feels. Petrolatum and petrolatum-containing mixtures are said to be favorable selections. The reference fails to teach or suggest the building of a deformable network of crystals within the benefit agent, and which crystals must have a specific aspect ratio. The Kacher reference fails to teach or suggest that the structured benefit agent be combined with other components in the compositions in a molten, semi-molten or solid state.
Also, it does not describe separate benefit agent and structurant as structurant, as is preferred by the subject invention (i.e., in the subject invention, if petrolatum is used, it is preferably used as a structurant to structure other benefit agents rather than itself comprise the structured benefit agent). In short, the benefit agents (e.g., oils) of Kacher clearly do not appear to be internally structured delivery vehicles like those used in the compositions of the invention which are separately prepared and wherein the structurant has defined aspect ratio.
A number of prior art references disclose generally the concept of an oil additive which can thicken or stabilize oils. They do not, however teach or disclose that specific crystalline structurant (i.e., having a defined aspect ratio), when prepared in combination with a benefit agent as a premix/delivery vehicle will enhance properties and/or sensory benefits of a separate hydrophobic benefit agent which is carried on or entrapped in the structured benefit agent, or which SHBA is found in the final formulation with the structured benefit agent.
U.S. Pat. No. 5,804,540 to Tsaur et al. and U.S. Pat. No. 5,661,189 to Grieveson, for example, disclose use of both crystalline or micro-crystalline waxes and hydrophobic polymers to thicken low viscosity oil so as to control the oil droplet size (i.e., it must attain a certain minimum size to deposit) as well as to maintain high lather. As noted above, however, there is no discussion of the criticality of crystalline structure (aspect ratio) or that a thickened benefit agent must be separately prepared and added in a molten, semi-molten or solid state for enhancing properties of a separate hydrophobic benefit agent. Further, as noted, there is no recognition that it is critical the thickener must be a crystalline structuring material, hydrogenated oil, fat, etc. (as defined in the subject invention)
In co-pending U.S. patent application Ser. No. 09/859,862 to Aronson et al. (entitled “Wet-Skin Treatment Composition”), filed May 17, 2001 and 09/859,849 to Aronson et al. (entitled “Method of Enhanced Moisture or Reduced Drying Using Wet-Skin Treatment Compositions”), there is disclosed benefit agents which provide a draggy feel. There is no teaching or disclosure, however, of using a benefit agent structured with crystalline materials of specific aspect ratio or of how to produce such.
No prior art of which applicants are aware demonstrates the use of structurants of the invention (e.g., wax, hydrogenated fats), having specific aspect ratio of crystals and prepared as a premix, to enhance properties (e.g., enhances perfume impact or skin lightening effect) of separate hydrophobic benefit agents (through the enhanced deposition of the structured benefit agent or other mechanism).